SHALLOW ELECTRICAL PROTECTION DEVICE (GFCI, AFCI, AND AFCI/GFCI) SYSTEM AND METHOD
A resettable switching apparatus, useful in a GFCI receptacle, has a housing with a face plate and at least one sense transformer core positioned to define a current flow direction through a center cavity that is parallel to the face plate. The GFCI receptacle further includes a space-efficient coaxial configuration in which a mechanical latching arrangement for resetting (i.e., closing) main switch contacts is disposed inside the trip solenoid. A movable carriage for the main contacts spans one end of the solenoid and has a latching portion in the solenoid that engages the inner end of a reset plunger in two sequential states (i.e., unlatched and latched). The mechanical latching arrangement comprises a cam surface coupled to a lifting plate, which is connected to the carriage of the GFCI receptacle. The cam surface is responsible for translating a downward movement to a translational movement to engage the carriage to the rest plunger.
This application claims priority to U.S. Provisional Patent Application No. 62/595,760, filed Dec. 7, 2017, the entire contents of which are expressly incorporated herein by reference.
This application contains subject matter related to subject matter contained in U.S. Pat. No. 8,830,015 B2 entitled, “COMPACT LATCHING MECHANISM FOR SWITCHED ELECTRICAL DEVICE,” by Kenny Padro et al., which is assigned to the assignee hereof, and the entire contents of which are expressly incorporated herein by reference.
FIELDEmbodiments relate to switched electrical devices, more particularly to circuit interrupting devices.
SUMMARYCircuit interrupting devices, such as ground fault circuit interrupter (GFCI) devices, switch to a “tripped” or unlatched state from a “reset” or latched state when one or more conditions is detected. GFCI devices having contacts that are biased toward the open position require a latching mechanism for setting and holding the contacts in a closed position. Likewise, switched electrical devices having contacts that are biased toward the closed position require a latching mechanism for setting and holding the contacts in an open position. Examples of conventional types of devices include devices of the circuit interrupting type, such as circuit breakers, arc fault interrupters, and GFCIs, to name a few.
Many electrical receptacles have built-in ground fault protection circuitry, i.e., GFCI receptacles. Such protection circuitry and the associated mechanisms normally take up a substantial amount of the physical space within a receptacle housing, the size of which is limited by the standard junction boxes in which they must fit. The embodiments disclosed in the present application attempt to solve these problems by providing more compact devices, allowing for shallower receptacles and more space for other elements and/or features.
One embodiment discloses an electrical outlet receptacle comprises a housing including a face plate and a plurality of sensing cores each configured to receive a current flow through a center cavity. The current flow defines a current flow direction through the center cavity, wherein the current flow direction is parallel to the face plate, and the plurality of sensing cores are placed symmetrically in a translational direction across the electrical outlet receptacle.
Another embodiment discloses an electrical outlet receptacle comprises a housing including a face plate and a sensing core configured to receive a current flow through a center cavity. The current flow defines a current flow direction through the center cavity of the sensing core, wherein the current flow direction is parallel to the face plate.
Another embodiment discloses an electrical outlet receptacle comprises a circuit board defining a first plane, a set of fixed contacts, a set of movable contacts, a solenoid having a central axis perpendicular to the first plane, a carriage movable axially along the solenoid and configured to interact with the set of movable contacts, a lifting shelf slidably coupled to a slot in the carriage and movable in a translational direction perpendicular to the central axis of the solenoid, a slide mechanism coupled to the lifting shelf and movable in the translational direction of the lifting shelf, a reset plunger with a portion extending through a first end of the solenoid and axially movable therein, and an armature movable axially along the portion of the reset plunger extending through the solenoid. The circuit board includes at least one contact pad. The solenoid includes a second end opposite the first end. The carriage is adapted to advance the set of movable contacts to form electrical communication with the set of fixed contacts during resetting of the electrical outlet receptacle. The lifting shelf includes a latching portion. The slide mechanism includes a cam surface to transform a downward force to a translational force applied to the coupled lifting shelf. The reset plunger includes an intermediate collar configured to engage to the latching portion of the lifting shelf. The armature includes a slanted projection configured to contact the cam surface of the slide mechanism and provide the downward force on the cam surface.
Other aspects of the application will become apparent by consideration of the detailed description and accompanying drawings.
The aspects and features of various exemplary embodiments will be more apparent from the description of those exemplary embodiments taken with reference to the accompanying drawings, in which:
Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The application is capable of other embodiments and of being practiced or carried out in various ways.
As described herein, terms such as “front,” “rear,” “side,” “top,” “bottom,” “above,” “below,” “upwardly,” and “downwardly” are intended to facilitate the description of the electrical receptacle of the application, and are not intended to limit the structure of the application to any particular position or orientation.
Exemplary embodiments of devices consistent with the present application include one or more of the novel mechanical and/or electrical features described in detail below. Such features may include a compactly positioned sensing core, a vertical solenoid, and a latching mechanism including a lifting shelf, a slide mechanism, an intermediate collar, and a cam surface. In some exemplary embodiments of the present application, multiple features listed above are incorporated into one element whereas in other exemplary embodiments, each feature is distinct from one another and coupled to interact with each other. The novel mechanical and/or electrical features detailed herein efficiently utilize the space within the device housing to provide more area for additional features and/or components.
Referring to
The resiliency of the cantilevered support provided by the bus bars 44, 46 bias the set of movable contacts 48A away from the set of fixed contacts 48B. A latching mechanism including a movable carriage, described in further detail in the following figures, is used to engage with the set of movable contacts 48A, thereby pushing the set of movable contacts 48A in an upward direction to engage the set of fixed contacts 48B in a closed position during resetting of the GFCI receptacle 10. This upward movement of the set of movable contacts 48A also causes corresponding upward movement in the attached phase and neutral terminals 30, 32 closer to the front cover 12 of the receptacle 10. Electricity may then be delivered from an external power source to the receptacle openings 16, 18, 20. In other embodiments, the resiliency of the cantilevered bus bars 44, 46 may bias the set of movable contacts 48A toward the set of fixed contacts 48B, and a latching mechanism may be employed in reverse to engage and hold the set of movable contacts 48A away from the set of fixed contacts 48B in an open position during tripping of the GFCI receptacle 10. The phase and neutral terminals 30, 32 will likewise increase in distance from the front cover 12, thereby prohibiting the flow of electricity between the external power source and the receptacle openings 16, 18, 20. Various embodiments of the latching mechanism may be used by various application designs, the details of each are not disclosed in detail herein.
Referring to
Referring to
Referring to
Two exemplary embodiments of the latching mechanism are shown in
In the one-piece latching mechanism of
According to one embodiment shown in
The GFCI receptacle 10 according to embodiments of the present application has four different states: 1) unlatched state or tripped state, 2) unlatched pushing state, 3) latched pulling state, and 4) latched state or reset state. During the tripped state of
Once a downward pushing force is received on the reset plunger 66 from a user pushing down on the reset button 24, the GFCI receptacle 10 enters the unlatched pushing state of
When the GFCI receptacle 10 is in the latched pulling state shown in
When the sense transformer cores 50, 51 detect the present of a fault, the GFCI receptacle 10 completes a tripping process. During the tripping process, the GFCI receptacle 10 experiences the states of the resetting process in reverse order, thereby unlatching the intermediate collar 78 from the latching portion 80 and breaking the electrical communication between the set of movable contacts 48A and the set of fixed contacts 48B.
In certain other embodiments, additional elements, such as springs, contacts, etc., may be included in various places within the GFCI receptacle 10 to accomplish resetting or tripping of the device. All combinations of embodiments and variations of design are not exhaustively described in detail herein. Said combinations and variations are understood by those skilled in the art as not deviating from the teachings of the present application.
Claims
1. An electrical outlet receptacle comprising:
- a housing including a face plate;
- a plurality of sensing cores each configured to receive a current flow through a center cavity, the current flow defining a current flow direction through the center cavity,
- wherein the current flow direction is parallel to the face plate, and
- wherein the plurality of sensing cores are place symmetrically in a translational direction across the electrical outlet receptacle.
2. An electrical outlet receptacle comprising:
- a housing including a face plate;
- a sensing core configured to receive a current flow through a center cavity, the current flow defining a current flow direction through the center cavity,
- wherein the current flow direction is parallel to the face plate.
3. The electrical outlet receptacle of claim 2, further comprising:
- a set of fixed contacts and a set of movable contacts;
- a solenoid having a central axis perpendicular to the face plate, a first end and a second end opposite the first end;
- a carriage movable axially along the solenoid and configured to interact with the set of movable contacts, the carriage configured to advance the set of movable contacts to form electrical communication with the set of fixed contacts during resetting of the electrical outlet receptacle;
- a reset plunger with a portion extending through the first end of the solenoid and axially movable therein, the reset plunger being biased toward a rest position away from the carriage; and
- an armature movable axially along the portion of the reset plunger extending through the solenoid, the armature being biased toward a rest position away from the carriage,
- wherein the reset plunger includes an engaging portion and the carriage includes a latching portion, the engaging portion of the reset plunger being configured to connect to the latching portion of the carriage.
4. The electrical outlet receptacle of claim 3, wherein the solenoid includes a coil bobbin with an inner coil and an outer coil.
5. The electrical outlet receptacle of claim 3, wherein the reset plunger further includes a spring configured to bias the reset plunger toward the rest position.
6. The electrical outlet receptacle of claim 3, wherein the armature interacts with the latching portion of the carriage when the solenoid is momentarily energized to cause engagement of the engaging portion to the latching portion in a latched state.
7. The electrical outlet receptacle of claim 6, wherein in the latched state, the armature interacts with the latching portion of the carriage when the solenoid is momentarily energized to cause disengagement of the engaging portion from the latching portion in an unlatched state.
8. The electrical outlet receptacle of claim 6, wherein pressing of the reset plunger causes the engaging portion to apply a downward force on the carriage at least until the electrical outlet receptacle is in the latched state, and subsequent release of the reset plunger causes the engaging portion to apply an upward force on the carriage to close the set of movable contacts and the set of fixed contacts.
9. The electrical outlet receptacle of claim 2, wherein the at least one sensing core includes a ground fault circuit interrupter (GFCI) core and an arc fault circuit interrupter (AFCI) core, the GFCI core having a first current flow direction and the AFCI core having a second current flow direction.
10. The electrical outlet receptacle of claim 9, wherein the first current flow direction and the second current flow direction are identical to each other.
11. The electrical outlet receptacle of claim 9, wherein the first current flow direction and the second current flow direction are substantially parallel to each other.
12. The electrical outlet receptacle of claim 9, wherein the first current flow direction and the second current flow direction are at an oblique angle to each other.
13. The electrical outlet receptacle of claim 9, wherein the first current flow direction and the second current flow direction are at a right angle to each other.
14. The electrical outlet receptacle of claim 9, wherein the GFCI core and AFCI core are positioned in a symmetrical placement across a translational direction of the electrical outlet receptacle, the symmetrical placement allowing for no interference of the GFCI core and the AFCI core with contact terminals connectable to an external device.
15. An electrical outlet receptacle comprising:
- a circuit board defining a first plane, the circuit board including at least one contact pads;
- a set of fixed contacts and a set of movable contacts;
- a solenoid having a central axis perpendicular to the first plane, a first end and a second end opposite the first end;
- a carriage movable axially along the solenoid and configured to interact with the set of movable contacts, the carriage being adapted to advance the set of movable contacts to form electrical communication with the set of fixed contacts during resetting of the electrical outlet receptacle;
- a lifting shelf slidably coupled to a slot in the carriage and movable in a translational direction perpendicular to the central axis of the solenoid, the lifting shelf having a latching portion;
- a slide mechanism coupled to the lifting shelf and movable in the translational direction of the lifting shelf, the slide mechanism having a cam surface to transform a downward force to a translational force applied to the coupled lifting shelf;
- a reset plunger with a portion extending through the first end of the solenoid and axially movable therein, the reset plunger having an intermediate collar configured to engage to the latching portion of the lifting shelf; and
- an armature movable axially along the portion of the reset plunger extending through the solenoid, the armature including a slanted projection configured to contact the cam surface of the slide mechanism and provide the downward force on the cam surface.
16. The electrical outlet receptacle of claim 15, wherein the solenoid includes a coil bobbin with an inner coil and an outer coil.
17. The electrical outlet receptacle of claim 15, wherein the slide mechanism includes a tab portion configured to apply the translational force to the lifting shelf.
18. The electrical outlet receptacle of claim 17, further comprising:
- a contact spring coupled to the lifting shelf and movable therewith, the contact spring being configured to send a signal when in electrical communication with the at least one contact pads of the circuit board; and
- a return spring coupled to the lifting shelf, the return spring having a maximum compression characteristic that limits movement in the translational direction of the lifting shelf.
19. The electrical outlet receptacle of claim 18, wherein pressing of the reset plunger causes the intermediate collar of the reset plunger to apply a push force on the latching portion of the lifting shelf at least until the contact spring forms electrical communication with the at least one contact pads of the circuit board in an unlatched pushing state.
20. The electrical outlet receptacle of claim 19, wherein
- when in the unlatched pushing state, the solenoid momentarily energizes, causing the slanted projection to move axially along the reset plunger and contact the cam surface to provide the downward force, which translationally moves the lifting shelf via the tab portion of the slide mechanism, and
- when the solenoid momentarily de-energizes, the slanted projection retracts axially along the reset plunger and the return spring pulls the lifting shelf back to its original position, causing engagement of the intermediate collar to the latching portion in a latched state.
21. The electrical outlet receptacle of claim 20, wherein in the latched state,
- when the solenoid momentarily energizes, the slanted projection moves axially along the reset plunger and contact the cam surface to provide the downward force, which translationally moves the lifting shelf via the tab portion of the slide mechanism, causing disengagement of the intermediate collar from the latching portion in an unlatched state, and
- when the solenoid momentarily de-energizes, the slanted projection retracts axially along the reset plunger and the return spring pulls the lifting shelf pulls back to its original position.
22. The electrical outlet receptacle of claim 20, wherein when the electrical outlet receptacle is in the latched state, subsequent release of the reset plunger pulls the lifting shelf and the carriage to form electrical communication between the set of movable contacts and the set of fixed contacts.
Type: Application
Filed: Dec 6, 2018
Publication Date: Jun 13, 2019
Patent Grant number: 11309667
Inventors: David Ridgeway (Milford, CT), Kenny Padro (Hamden, CT)
Application Number: 16/212,141